Heat 3 Tbsp.,butter in heavy medium pot over medium-high heat.,Add in broccoli stems and onion; saute/fry till onion is translucent/soft, about 6 min.,Add in garlic and tarragon; saute/fry 1 minute.,Add in stock; bring to boil.,Simmer uncovered till broccoli is tender, about 15 min.,Stir in cream.,Mix remaining 3 Tbsp.,butter with flour in small bowl to make paste.,Whisk paste into soup.,Add in broccoli florets.,Simmer till soup thickens and florets are tender, stirring frequently, about 5 min.,(Can be made 1 day ahead.,Cold slightly, then chill uncovered till cool.,Cover and keep refrigerated.,Bring to simmer before continuing.),Preheat broiler.,Place 6 ovenproof soup bowls on baking sheet.,Divide soup among bowls.,Sprinkle 1/3 c. cheese over each.,Broil till cheese melts and bubbles around edges, about 4 min.,______,Comments: "As a student at Bloomsburg University, I spent many Sunday afternoons at Russell"s restaurant in downtown Bloomsburg, Pennsylvania," writes Marganne Hoffman of Lebanon, Pennsylvania.,"A decade after graduating, I still crave their cheddar-crusted broccoli soup.,I would be thrilled if the owners would share the recipe-and so would my family.",The stems and florets are added to the soup separately so which the stems will cook till tender and the florets won"t overcook.